I just found this forum and glad I did.
Marcia you state that your later subsequent firings only took 3.5 minutes to reach temp. Am I reading that right?
I take almost the same time in second,3rd,4th etc firings as I do in my first.
I have a 23X36 4 section ^10 two burner gas kiln. I modified the jets ( opened them up) to accommodate propane. And only run 3 rings but have ran it for a day with just 2 rings in and did not like the process so I went back to 3 rings. I have not made anything tall enough to run all 4 rings in a Raku firing and have never ran a ^10 reduction firing with it.
I usually take around an hour on the first firing then set my new work in the kiln and let it soak in the 600- 700 deg F kiln. After 10 minutes or so I light one of my two burners till I get to around 1000 deg F then take my time till I get to 1850-1900 then shut off the gas and pull the pieces.
I have played with reduction in the kiln as I am firing and know that slows things down also. I put it into reduction around 1500 deg F and hold it there until I reach my desired temp. The last few minutes I let it clear out just a bit by pulling back my baffle plate on the top. I only do this when working with a glaze that has some copper in it not in any of the crackle glaze I have used.
Prior to running my own kiln I had only been around one raku firing and so I have a lot to learn as is the case when one is new to anything.
I have cracked some of my work and I thought it was from to quick of a ramp up to max heat. I think the other reason is some of my work is still too think, new potter style thick.
I am open to anyone's thoughts on my processes and techniques in my firings.
Thanks everyone and again really glad I found this forum.